EP2050150B1 - Method for producing at least one multilayer body, and multilayer body - Google Patents

Description

The invention relates to a method for producing a multilayer body, in particular a multilayer body having at least one electronic component, wherein the multilayer body comprises at least two functional layers, in particular electrical functional layers, on an upper side of a carrier substrate, which are structured in register with one another. The invention further relates to a multi-layer body obtainable thereafter.

US 2004/0009413 describes black and white masks for structuring micromechanical devices.

DE 10 2004 059 467 A1 describes electronic components in the form of organic field effect transistors (OFET), which are connected to a logic gate and their preparation on a carrier substrate. The field-effect transistors are formed from a plurality of functional layers or functional layers, which are applied to the carrier substrate, in particular by printing or knife coating. The carrier substrate is formed inter alia as a plastic film with a thickness in the range of 6 to 200 microns.

Thick support substrates have heretofore been preferred because processing of thinner, less costly support substrates having a thickness in the range of 6 to about 50 microns has been found to be prone to distortion during processing, with the distortion varying with each processing step. If an electrical functional layer is applied and patterned on the thin carrier substrate, a noticeable distortion or perpendicular to the carrier substrate already results in a deviation of the shape of the functional layer from its ideal shape. The delay has a particularly disturbing effect if, subsequently or after application of one or more full-surface functional layers, combined with a further change in the dimensions of the already formed structured functional layer, a further structured functional layer must be arranged in the register relative to the already formed structured functional layer.

It is therefore an object of the invention to provide an improved method for producing a multilayer body with functional layers structured in register with one another and components which can be produced thereafter, in particular to provide an improved method for producing electronic components on carrier substrates which are prone to warping.

The object is achieved for the method for producing a multilayer body, which comprises at least two, in particular electrically functional layers on an upper side of a carrier substrate, which are structured in register to each other, that a bottom of the carrier substrate is prepared such that in a first region, a permeability for a first exposure radiation and in at least one second region, a transmission for at least one different second exposure radiation in the register to the first region results in that the bottom is successively exposed to the first and the at least one second exposure radiation, and that the first exposure radiation for structuring a first functional layer and the at least one second exposure radiation is used for structuring at least one second functional layer on the upper side of the carrier substrate.

Despite the distortion of the carrier substrate during its processing, the method according to the invention makes possible an unproblematic arrangement of the at least one second functional layer in the perfect or nearly perfect register to the first functional layer, since the distortion occurring equally affects the first region and the at least one second region. The shape of the first region is changed perpendicular to the plane of the carrier substrate in accordance with the shape of the at least one second region by the distortion, so that the position of the first region with respect to the position of the at least one second region can not shift. The position of the first region and of the at least one second region is thus already established on the carrier substrate at the beginning of the production process, so that an inaccuracy in the orientation of the first functional layer relative to the at least one second functional layer can no longer occur despite a distortion of the carrier substrate. The at least one second functional layer is formed in a position that is different from its ideal shape and in a shape adapted to the currently present form of the first functional layer, in a positionally accurate manner relative to the first functional layer. Due to the precise positioning of the functional layers relative to one another, it is now possible to form high-quality optical and / or electrical components with improved optical or electrical properties while at the same time requiring less space on the carrier substrate.

Thus, in the production of OFETs on a thin carrier substrate due to the optimal alignment of the source / drain electrodes relative to the gate electrode significantly lower gate capacitances are achieved, so that a switching speed of the OFETs is significantly increased. While approximately 80% of the surface of the carrier substrate was lost in the consideration of tolerances in the production of the individual functional layers in the earlier production methods, a significantly better utilization of the surface of the carrier substrate is now possible, meaning that up to 100% more electronic components are possible a carrier substrate can be formed.

The method according to the invention is furthermore particularly suitable for the production of optical components which comprise two structured functional layers separated from one another by a spacer layer. The two structured functional layers may be metallic or colored layers. The first functional layer is preferably an opaque mask layer which, when viewed, effects an angle-dependent geometrical shadowing of the second structured functional layer and thus generates, for example, a color flip or a change in the displayed image information depending on the viewing angle. Again, it is possible that the two or more independently structurable functional layers are directly adjacent to each other and thus form, for example, a color image by additive or subtractive color mixing. The functional layers may also be IR or UV-luminescent layers structurable independently of one another or layers which are provided with optically variable pigments (thin-film layer pigments, liquid crystal pigments). Furthermore, it is also possible for the optical functional layers to be superimposed on a diffractive surface relief and thus represent, for example, metallic or dielectric reflection layers which enable the generation of a partially present optically variable effect (for example a hologram).

It can be provided to provide the carrier substrate on the underside directly with relief structures or to provide a layer applied to the underside, in particular of a thermoplastic material or a UV coating, with relief structures. In this case, an injection molding tool can be used or the relief structures can be formed by molding a stamp in UV varnish or by means of an optionally heated stamp in thermoplastic material. Also, the use of a classical photolithography method to form the relief structures on the bottom Of the carrier substrate, in which a photoresist is applied, exposed, developed and used as an etching mask for the bottom, is readily possible.

The object is achieved for a multilayer body, in particular comprising an organic electronic component, which has a carrier substrate made of a flexible film material, in particular a plastic film material, characterized in that an underside of the carrier substrate is prepared such that in a first region, a permeability to a first At least two structured functional layers in register with each other and further in the register to the first and the at least one second on a top side of the carrier substrate at least one second exposure radiation is formed in the register to the first region Area are arranged.

The carrier substrate in this case has a thickness in the range of 3 .mu.m to 250 .mu.m, preferably 6 .mu.m to 50 .mu.m.

The first and second exposure radiation may differ, for example, by their wavelength, polarization, spectral composition, the angle of incidence of illumination, etc.

Due to the precise positioning of the functional layers relative to one another, the component has particularly good and reproducible optical and / or electrical properties while at the same time requiring little space.

In a first variant of the inventive method, the underside of the carrier substrate is prepared by a first relief structure in the first region and in the second region and in register with the first relief structure at least one second relief structure different from the first relief structure is formed so that an exposure mask layer is applied to the underside, wherein the exposure mask layer is applied with a constant areal density relative to a plane spanned by the carrier layer, that in the register to the first relief structure that on top The first functional layer applied to the carrier substrate is structured, and the at least one second electrical functional layer applied to the upper side of the carrier substrate is patterned in register with the at least one second relief structure. In this embodiment of the invention, no exposure mask layer is needed.

The first variant of the method is based on the finding that physical properties of the exposure mask layer applied to the carrier substrate, for example effective thickness or optical density, are influenced by the relief structures in the first and at least one second area, so that the transmission properties of the exposure mask layer in the first and second area differ. The exposure mask layer is used in an exposure method as a mask for the partial removal of the first electrical functional layer and also for the partial removal of the at least one second electrical functional layer, in each case by passing a photosensitive layer on the upper side of the carrier substrate through the exposure mask layer, ie also through the carrier substrate is exposed and partially removed, so that a structuring of the first and the second functional layer is carried out immediately or can be done afterwards.

As a result, compared to the functional layers applied with conventional methods, the advantage is achieved that they are aligned in register with each other without additional adjustment effort. Only the Tolerances of the relief structures Influence on the tolerances of the position of the two functional layers. The arrangement of areas of the exposure mask layer with the same physical properties takes place exactly in register with the first and at least one second area.

The carrier substrate should be as thin as possible, since the distance between the structured layer and the e.g. photoactive layer on the opposite side, especially with thick carriers, may have an impact on the quality / resolution / register of the functional layer.

The exposure mask layer is a layer that performs a dual function because it provides the function of a high-precision exposure mask for the manufacturing process of differently structured functional layers.

The exposure mask layer is preferably applied to the carrier substrate by means of sputtering, vapor deposition or spraying. When sputtering is due to the process, a directed material order, so that when sputtering material of the exposure mask layer in constant area density based on the plane spanned by the carrier substrate plane, the material is locally deposited differently thick on the provided with the relief structures carrier substrate. During vapor deposition and spraying of the exposure mask layer, an at least partially directed material application is preferably also produced by process engineering. The material application can be done not only vertically, but also at an angle in the range of 30 to 150 ° to the plane spanned by the carrier substrate level. This is particularly advantageous when using periodic symmetric or asymmetrical relief structures, which are selectively coated in a targeted manner should be.

In this case, the exposure mask layer is preferably formed by a metal layer or by a layer of a metal alloy. Such layers can be applied by known methods, such as sputtering, and they have a sufficient optical density even at low layer thicknesses. However, the exposure mask layer can also be a nonmetallic layer, which can be colored, for example, can contain liquid crystals or can be doped, for example with nanoparticles or with nano spheres, in order to increase their optical density.

It can further be provided that the exposure mask layer is applied to the carrier substrate in a thickness at which the exposure mask layer is substantially opaque, preferably has an optical density of greater than 1.5.

Surprisingly, it has been shown that increasing the opacity of the exposure mask layer can increase the ratio of the transmissivities of the regions with different diffractive relief structure. If exposure is effected with an appropriate illuminance by an exposure mask layer (for example optical density of 5), which is normally designated as opaque, which would normally not be used as a mask layer because of its high optical density, particularly good results can be achieved.

It is particularly advantageous if the exposure mask layer is applied to the carrier substrate over its entire surface in a thickness at which the exposure mask layer has an optical density between 2 and 7. For the formation of particularly large differences in the optical density of the first and the second relief structure may be in the first region as a first relief structure, a diffractive relief structure with a high depth-to-width ratio of the individual structural elements, in particular with a depth-to-width ratio> 0.3, molded and the second relief structure be formed as a relief structure with lower depth-to-width ratio.

By using such special diffractive relief structures, it is possible, with a suitable choice of the layer thickness of the exposure mask layer, to generate very large differences in the optical density of the first layer in the first region and in the second region which are already recognizable with the eye. Surprisingly, however, it was found that such large differences in the transmission in the first and in the second range for the implementation of the inventive method are not mandatory. It is only important that the first and the at least one second region delimit by their transmission properties or a lower or a greater optical density.

In an advantageous embodiment, it is provided that the photosensitive layer is exposed through the exposure mask layer by means of UV radiation. Experiments have shown that the differences in the transmission properties of the exposure mask layer in the region of the UV radiation which can be achieved by the different design of the relief structure in the first and second regions are particularly pronounced. When using UV radiation for the exposure, particularly good results can be achieved.

Relief structures with small differences in the depth-to-width ratio also usually show relatively small differences in transmission with thin vapor deposition. Even small relative differences However, they can be enhanced by increasing the layer thickness of the exposure mask layer and thus the average optical density. Thus, even with quite small differences in the transmission of the exposure mask layer in the first and in the second range, good results can be achieved. The exposure mask layer may be a very thin layer, on the order of a few nm. The exposure mask layer applied with uniform areal density relative to the plane defined by the carrier substrate is made substantially thinner in areas having a high depth-to-width ratio than in areas having a lower depth-to-width ratio.

The dimensionless depth-to-width ratio h / d is a characteristic feature for the enlargement of the surface when using preferably periodic structures, for example with a sinusoidal course. Depth is the distance between the highest and the lowest consecutive point of such a structure, ie the distance between "mountain" and "valley". Width is the distance between two adjacent highest points, ie between two "mountains". The higher the depth-to-width ratio, the steeper the "mountain flanks" and the thinner the first layer deposited on the "mountain flanks". The effect of forming higher transmission or transparency as the depth-to-width ratio increases is also observed in structures having vertical edges, such as rectangular gratings. But they can also be structures to which this model is not applicable. For example, they may be discretely distributed line-shaped areas which are formed only as a "valley", wherein the distance between two "valleys" is many times higher than the depth of the "valleys". In formal application of the above definition, the thus calculated depth-to-width ratio would be close to zero and do not reflect the characteristic physical behavior. Therefore, with discretely arranged structures formed essentially only of a "valley", the depth of the "valley" should be related to the width of the "valley".

The degree of optical density reduction may vary depending on the background, lighting, etc. An important role is played by the absorption of light in the exposure mask layer.

Table 1 shows the determined reflectance of between plastic films (refractive index n = 1.5) arranged exposure mask layers of metal, in particular Ag, Al, Au, Cr, Cu, Rh and Ti at a light wavelength λ = 550 nm. The thickness ratio ε is in this case formed as the quotient of the thickness t of the metal layer required for the reflectance R = 80% of the maximum R _max and for the reflectance R = 20% of the maximum R _max . Table 1 metal R _Max t for 80% R _Max t for 20% R _Max ε h / d Ag 0.944 31 nm 9 nm 3.4 1.92 al 0.886 12 nm 2.5 nm 4.8 2.82 Au 0.808 40 nm 12 nm 3.3 1.86 rh 0.685 18 nm 4.5 nm 4.0 2.31 Cu 0.557 40 nm 12 nm 3.3 1.86 Cr 0,420 18 nm 5 nm 3.6 2.05 Ti 0,386 29 nm 8.5 nm 3.3 1.86

From the heuristic point of view, as can be seen, silver and gold (Ag and Au) have a high maximum reflectance R _Max and require a relatively small depth to width ratio to reduce the optical density of the metallic exposure mask layer in the above Example of training for transparency. Although aluminum (Al) also has a high maximum reflectance R _Max , it requires a higher depth-to-width ratio. Preferably, therefore, it may be provided to form the exposure mask layer of silver or gold.

Table 2 now shows the calculation results obtained from strict diffraction calculations for relief structures formed as linear, sinusoidal gratings with a grid spacing of 350 nm with different depth-to-width ratios. The relief structures are coated with silver with a nominal thickness t ₀ = 40 nm. The light impinging on the relief structures has the wavelength λ = 550 nm (green) and is TE polarized or TM polarized. Table 2 Depth-to-width ratio Grid spacing in nm Depth in nm Reflectance (0R) TE Degree of transparency (0T) TE Reflectance (0R) TM Degree of transparency (0T) TM 0 350 0 84.5% 9.4% 84.5% 9.4% 0.3 350 100 78.4% 11.1% 50.0% 21.0% 0.4 350 150 42.0% 45.0% 31.0% 47.0% 1.1 350 400 2.3% 82.3% 1.6% 62.8% 2.3 350 800 1.2% 88.0% 0.2% 77.0%

As it turned out, apart from the depth-to-width ratio, the transmission is also dependent on the polarization of the radiated light. This dependence is shown in Table 2 for the depth to width ratio h / d = 1.1. It may be provided to use this effect for the selective formation of functional layers.

Furthermore, it was found that the degree of transparency or the reflectance of the exposure masks is wavelength-dependent. This effect is especially good for TE polarized light.

Furthermore, it has been found that the degree of transparency or transmission decreases when the angle of incidence of the light differs from the normal angle of incidence, i. the degree of transparency decreases when the light is not incident vertically. This means that the exposure mask layer can be made transparent or transparent only in a limited incidence cone of the light. It can thus be provided that the exposure mask layer is formed opaque or impermeable in oblique illumination, whereby this effect can be used for the selective formation of further functional layers.

In addition to the depth-to-width ratio of a relief structure, the change in the optical density is also influenced by the spatial frequency of the relief structure. It has thus been further shown that a change in the transmission behavior of an exposure mask layer applied to a relief structure can be achieved if the product of spatial frequency and relief depth in a first region of the relief structure is greater than the product of spatial frequency and relief depth in a second region of the relief structure.

• die Polarisationsabhängigkeit der Transmission infolge unterschiedlich orientierter Strukturen;
• den Formfaktor der Strukturen, d.h. Strukturen mit rechteckförmigem, sinusförmigem, sägezahnförmigem oder sonstigem Profil können bei gleichem Produkt aus Spatialfrequenz und Relieftiefe eine unterschiedliche Transmission aufweisen;
• gerichtetes Aufdampfen der Belichtungsmaskenschicht in Kombination mit speziellen Strukturen bzw. Strukturkombinationen oder Strukturanordnungen.

The formation of regions of different transparency or transmission can also be achieved by other effects, for example by

• the polarization dependence of the transmission due to differently oriented structures;
• the form factor of the structures, ie structures with rectangular, sinusoidal, sawtooth or other profile can have a different transmission with the same product of Spatialfrequenz and relief depth;
• directed vapor deposition of the exposure mask layer in combination with special structures or structural combinations or structural arrangements.

If the first relief structure is a structure with a stochastic profile, for example a matt structure, the correlation length, roughness depth and statistical distribution of the profile can be typical parameters which influence the transmission.

In order to form regions with different transparency or transmission, it is thus also possible to use relief structures in the first region and in the second region which differ in one or more of the parameters listed above.

In a second variant of the method according to the invention, the underside of the carrier substrate is prepared by forming a first relief structure in the first region and at least one second relief structure different from the first relief structure in the second region and in register with the first relief structure Relief structure is structured on the top of the carrier substrate applied first functional layer and that in the register to the at least one second Relief structure, the at least one applied to the top of the carrier substrate second functional layer is structured.

The different exposure properties arise here due to the different diffraction, refraction or reflection of the exposure radiation to the relief structures formed.

The first and second exposure radiation preferably differs in this embodiment in their angle of incidence and / or in their wavelength. Thus, it is possible, for example, to provide lens structures, for example cylindrical lenses or free-form lenses, as the first and second relief structures, which focus the incident light in the first region or in the second region with different incidence of the exposure radiation and thus the permeability of the carrier substrate in the first and second relief structures increase the second range depending on the exposure direction. Furthermore, it is possible to provide diffractive relief structures on the underside of the carrier substrate, which focus the light as a function of angle of incidence and / or of the wavelength by diffraction in different regions. Thus, it is firstly possible to provide diffractive lenses which have a different focus depending on the wavelength of the incident light and thus the light at a first exposure radiation in the first region and at a second exposure radiation which differs from the first exposure radiation in its wavelength to focus in the second area. Furthermore, it is possible to use blaze gratings, which are characterized by a sawtooth-shaped relief profile. In this case, it is possible to choose the angle of incidence with respect to the edges of the sawtooth such that at a first angle of incidence of the light a total reflection (when applying a special LRI layer (on the bladder structure) - (LRI = Low Refractive Index) - on the flank of the sawtooth takes place and at a second angle of incidence of the light Beams are directed to the determined by the refractive angle range. Furthermore, it is possible to achieve, by a suitable choice of the blaze parameters (depth, period, material, etc.), that at least a significant difference in the transmitted intensity exists for the two angles of incidence.

Furthermore, it is also possible for the first and second relief structures to be provided with an optical separation layer, for example an HRI layer (for example ZnS).

By means of the first and second variant of the method, structured functional layers of very high resolution can be achieved. The achievable registration and resolution is about 100 times better than achievable by known structuring method. Since the width of the structural elements of the first relief structure can be in the range of the wavelength of the visible light (approximately 380 to 780 nm), but also below it, functional layer areas can be formed with very fine contours. Thus, great advantages over the previously used methods are achieved in this regard, as a further miniaturization of the device can be done.

It is possible to produce lines and / or dots with high resolution, for example with a width or a diameter of less than 5 μm, in particular up to approximately 200 nm. Preferably, resolutions in the range from approximately 0.5 μm to 5 μm, in particular in the Range of about 1 micron, generated. In contrast, with methods that provide an adjustment of the structured functional layers in the register, line widths smaller than 10 microns can be realized only with great effort.

It is preferred if the first and / or the at least one second relief structure are formed as diffractive relief structures. It has proven useful if the first and the at least one second relief structure differ in their azimuth.

• Lineargitter: z.B. Sinusgitter mit Linienzahlen von 100 l/mm bis 5000 l/mm und Strukturtiefen von 50 nm bis 5 um.
• Kreuzgitter: z.B. Sinusgitter mit Linienzahlen von 100 l/mm bis 5000 l/mm und Strukturtiefen von 50 nm bis 5 µm.
• Mattstrukturen (isotrop/anisotrop): Korrelationslängen von 0,5 µm bisss 50µm und Strukturtiefen von 50 nm bis 10 µm.
• Blazegitter oder Mikroprismen: Linienzahlen von 10 l/mm bis 3000 l/mm und Strukturtiefen von 25 nm bis 10µm.
• Makrostruktur: beliebig geformte Oberflächenstrukturen, charakterisiert durch maximale Tiefe von 100 nm bis 10µm, mit grossen Entfernungen (≥ 100 µm) zwischen Unsteigkeitsstellen des Oberflächenprofils.
• Kombinatonsstrukturen: ergeben sich aus Kombinationen oben genannter Strukturen.

The first and / or the at least one second relief structure are in particular formed as a lattice structure, such as a linear lattice or cross lattice, as an isotropic or anisotropic matt structure, as a binary or continuous Fresnel lens, as a microprism, as a blazed lattice, as a combination structure or as a macrostructure:

• Linear grids: eg sine grids with line numbers from 100 l / mm to 5000 l / mm and structure depths from 50 nm to 5 μm.
• Cross gratings: eg sine gratings with line numbers from 100 l / mm to 5000 l / mm and structure depths from 50 nm to 5 μm.
• Matt structures (isotropic / anisotropic): Correlation lengths of 0.5 μm to 50 μm and structure depths of 50 nm to 10 μm.
• Blaze grates or microprisms: Line numbers from 10 l / mm to 3000 l / mm and structure depths from 25 nm to 10μm.
• Macrostructure: arbitrarily shaped surface structures, characterized by a maximum depth of 100 nm to 10 μm, with large distances (≥ 100 μm) between points of elevation of the surface profile.
• Combination structures: result from combinations of the above-mentioned structures.

According to a third variant of the method according to the invention, the underside of the carrier substrate is prepared by arranging a first color layer in the first region and at least one second color layer different in color from the first color layer in the second region and in register with the first color layer, and in the register for the first color layer, the first functional layer applied to the upper side of the carrier substrate is structured, and in the register to the at least one second color layer the at least one second electrical functional layer applied to the upper side of the carrier substrate is structured. The different color layers act as filters for exposure radiation of different wavelengths.

In this case, for example, a red color layer is pattern-shaped in the first area, which is permeable to a blue first exposure radiation, and printed in a second area, a blue color layer which is transparent to a red second exposure radiation. Both of the first and second color layer free areas of the carrier substrate let both exposure radiation through, while areas which are covered with two color layers, neither of the two exposure radiation pass.

According to the first, second or third variant, the first functional layer is preferably applied over the full area to the upper side of the carrier substrate, wherein a first photosensitive layer is formed over the whole area before or after formation of the first functional layer on the upper side. Thereafter, the first photosensitive layer is exposed by the first exposure radiation through the carrier substrate and optionally the exposure mask layer, which is permeable to the first exposure radiation in the first region, and the first photosensitive layer Layer is partially removed in the register to the first area, wherein structuring of the first functional layer takes place directly or subsequently. Furthermore, the at least one second functional layer is applied over its entire surface to the upper side, wherein at least one second photosensitive layer is formed over its entire surface before or after formation of the at least one second functional layer. Now, the at least one second photosensitive layer is exposed by at least the second exposure radiation through the carrier substrate and optionally the exposure mask layer, which is permeable to the second exposure radiation in the second region, and the at least one second photosensitive layer is registered Partially removed to the second region, wherein structuring of the at least one second functional layer takes place directly or subsequently.

It has proven useful if the underside of the carrier substrate is prepared in a third region such that the third region is permeable to both the first and the at least one second exposure radiation. As a result, regions of the structured first and the at least one structured second functional layer can be arranged congruently one above the other. In the case of the first and second variant with relief structures, the different relief structures in the third area are formed next to each other or superimposed. In the case of the third variant, no color layers are arranged in the third area.

Furthermore, it has proven useful if the underside of the carrier substrate is prepared in a fourth region such that the fourth region is impermeable to the first and at least one second exposure radiation. In the case of the first and second variant with relief structures are no or selected relief structures formed in the third region. In the case of the third variant, all color layers are arranged in the third area.

1. a) Belichten nur im ersten Bereich;
2. b) Belichten nur im mindestens einen zweiten Bereich;
3. c) Belichten im ersten und im mindestens einen zweiten Bereich;
4. d) nicht Belichten;

Thus, at least four different exposure states can be realized:

1. a) exposure only in the first area;
2. b) exposing only in at least a second area;
3. c) exposing in the first and at least a second area;
4. d) not exposing;

It has proven useful if the unprepared carrier substrate is formed from a material and / or in a thickness such that it is permeable to the first and / or the at least one second exposure radiation. However, the unprepared carrier substrate can also be formed so that it is impermeable to the first and / or the at least one second exposure radiation and only by the preparation, for example by the introduction of relief structures, or during exposure, for example by chemical reactions, etc., at least partially permeable to the exposure radiation.

It has proven useful if the first and the at least one second exposure radiation differ in their wavelength and / or their polarization and / or their impact angles on the plane spanned by the carrier substrate.

Thus, for the third variant of the method according to the invention, in particular exposure radiation of different wavelengths is used, for example red radiation as the first exposure radiation and blue Radiation than the at least one second exposure radiation in combination with a blue and a red color layer as first and second color layers.

Between the structured first and the at least one structured second functional layer, at least one third functional layer can be formed over the whole area or partially interrupted. It has proven useful if the at least one third functional layer is formed from a semiconducting or an electrically insulating functional layer material.

In general, functional layers, as well as the carrier substrate, which lie between the irradiation light source and a photosensitive layer in the beam path, must have a minimum permeability for the respective exposure radiation, so that a partial exposure of the photosensitive layer can take place. Not only the visual impression (opaque - transparent) is decisive, but only the transmission of the respective layer.

Preferably, the first functional layer is formed from an electrically conductive functional layer material in order to form in particular conductor tracks and / or electrode surfaces.

The structured second functional layer is formed, depending on the requirement of the formed component, of an electrically conductive or a semiconductive or a dielectric functional layer material.

In general, electrically conductive functional layers can be galvanically reinforced in an intermediate step in order to increase the electrical conductivity increase.

For the three variants, it has also proven useful if at least one photosensitive layer is used as the electrical functional layer. After its structuring, the photosensitive layer can, for example, form an electrically conductive layer, a semiconducting layer or a dielectric layer. Furthermore, at least one photosensitive layer may be removed during or after the process has been carried out.

It is preferred if a photosensitive washcoat layer or a positive or negative photoresist layer or a photopolymer layer is used as the photosensitive layer. Positive photoresists can be removed in the exposed area, negative photoreists in the unexposed area. A photosensitive layer, which is activated by the exposure and forms an etchant for the first and / or the at least one second functional layer in the activated regions, has proven itself.

Preferably, a capacitor is formed as the electronic component, wherein the first functional layer is formed electrically conductive and structured in the form of two capacitor electrodes and the at least one second functional layer is formed in the form of a structured dielectric layer.

Furthermore, it is preferred if a field-effect transistor, in particular an OFET, is formed as the electronic component, wherein the first functional layer is designed to be electrically conductive and structured in the form of source / drain electrodes, wherein a second functional layer is electrically conductive and in the form of a gate. Electrode is formed structured, or vice versa, and wherein between the first and the at least one second Functional layer over the entire surface of a third functional layer of a semiconductive layer and the entire surface of a fourth functional layer are formed of a dielectric layer. In this case, a top-gate or a bottom-gate structure can thus be selected.

The field-effect transistor is formed, in particular, by applying a photosensitive washcoat layer over the entire surface by forming the first functional layer over its entire surface so that the exposure is effected with the first exposure radiation, the washcoat layer becoming insoluble in the first region washed off including the first functional layer in the other areas and first functional layer is structured, that subsequently the third and the fourth functional layer are formed, further that the second functional layer and then a photoresist layer are applied over the entire surface, that now takes place exposure to the second exposure radiation and the Photoresist layer is patterned in the register to the second region, and in that using the patterned photoresist layer as an etching mask etching and patterning of the second functional layer is carried out.

Alternatively, the field effect transistor can be formed by the entire surface of the first functional layer formed on the top of the carrier layer and a first photoresist layer is applied over the entire surface, that now takes place exposure to the first exposure radiation, that the first photoresist layer structured in the register to the first region and as an etching mask for Etching and patterning of the first functional layer is used, that the etching mask is removed, that then the third functional layer and the fourth functional layer are formed, that further the second functional layer and thereon a second photoresist layer be applied over the entire surface, that now takes place the exposure with the second exposure radiation and the second photoresist layer is patterned in the register to the second area, and that using the patterned second photoresist layer as an etching mask etching and patterning of the second functional layer is carried out.

It has proven particularly advantageous if an organic electrical component containing at least one organic functional layer is formed.

The organic functional layer is preferably applied from a liquid, in particular by printing or knife coating. Organic functional layer materials may include polymers that are dissolved in the liquid. The liquid containing the organic functional layer materials may also be a suspension or emulsion.

An organic electrical functional layer may include all types of materials except the classical semiconductors (crystalline silicon or germanium) and the typical metallic conductors. A restriction in the dogmatic sense to organic material in the sense of carbon chemistry is therefore not provided. The term "polymer" expressly includes polymeric material and / or oligomeric material and / or "small molecule" material and / or "nano-particle" material. Layers of nanoparticles can be applied, for example, by means of a polymer suspension. Thus, the polymer may also be a hybrid material, for example to form an n-type polymeric semiconductor. Rather, for example, silicones are included. Furthermore, the term should not be limited in terms of molecular size, but, as stated above, include "small molecules" or "nano-particles". It can be provided that the organic functional layer is formed with different organic material.

As p-type organic semiconductor materials pentacene, polyalkylthiophene, etc. may be provided as n-type organic semiconductor materials z. B. soluble fullerene derivatives.

At least two electronic components are preferably formed on the carrier substrate. These can also be formed interconnected as part of an electronic circuit.

In particular, the carrier substrate is formed from a cost-effective flexible film material, in particular a transparent plastic film material, with a layer thickness in the range of 3 μm to 150 μm. Films made of PET, PC, PEN are particularly preferred. However, the use of rigid substrates, for example of glass, is also possible.

It is particularly preferred if the carrier substrate is strip-shaped and processed in a continuous roll-to-roll process. In this case, the carrier substrate is provided wound on a supply roll, withdrawn from this and coated in the inventive method with the functional layers of the at least one electrical component and finally wound up again on a further supply roll or divided into individual components, component groups or circuits, in particular by punching.

In a further embodiment, the carrier substrate may be detachable from the electrical functional layers of the component. For this purpose, in particular a release layer between the carrier substrate and the provided electrical functional layers of the at least one electrical component. A component or a component group can be fastened on a separate carrier by means of an adhesive layer, which is arranged on the side of the component which is opposite the carrier substrate, and subsequently the carrier substrate can be pulled off. The processing can be carried out by means known for transfer films method. The functional layers including the adhesive layer function as a transfer layer.

An inventive electronic component or its structured functional layers may have a delay in the range of 0 to 10% due to the small thickness of the carrier substrate. The distortion is calculated from the shape deviation of the structured functional layer with regard to its ideal shape.

The electronic component formed adapts particularly flexible to a device contour or the like, so that in particular a use for RFID tags on packaging material, labels or the like is possible.

The electronic component is preferably designed as a capacitor, a field effect transistor, in particular an OFET, an LED, in particular an OLED, or as a diode.

The formation of electronic circuits, in particular organic electronic circuits, with at least one electronic component according to the invention is ideal. In this case, the circuit can be formed such that it flexibly adapts to a device contour or the like.

Figur 1a

eine präparierte Unterseite eines Trägersubstrats;

Figur 1b

das Trägersubstrat aus Figur 1 im Schnitt A - A';

Figur 1c

die Oberseite des Trägersubstrats aus Figur 1a bei Belichtung mit einer ersten Belichtungsstrahlung;

Figur 1d

die Oberseite des Trägersubstrats aus Figur 1a bei Belichtung mit einer zweiten Belichtungsstrahlung;

Figur 2a

das Trägersubstrat aus Figur 1 im Schnitt A - A' mit darauf aufgebrachter erster Funktionsschicht und erster negativer Photoresistschicht;

Figur 2b

das Trägersubstrat aus Figur 2a nach Strukturierung der Photoresistschicht und Ätzen der ersten Funktionsschicht;

Figur 2c

das Trägersubstrat aus Figur 2a nach Entfernung der ersten Photoresistschicht in der Draufsicht;

Figur 2d

das Trägersubstrat aus Figur 2c mit darauf aufgebrachter zweiter Funktionsschicht und zweiter positiver Photoresistschicht;

Figur 2e

das Trägersubstrat aus Figur 2d nach Strukturierung der zweiten Photoresistschicht und Ätzen der zweiten Funktionsschicht; und

Figur 2f

das Trägersubstrat aus Figur 2e nach Entfernung der zweiten Photoresistschicht in der Draufsicht.

The FIGS. 1a to 2f should exemplify the process of the invention. So shows:

FIG. 1a

a prepared underside of a carrier substrate;

FIG. 1b

the carrier substrate FIG. 1 in section A - A ';

Figure 1c

the top of the carrier substrate FIG. 1a when exposed to a first exposure radiation;

Figure 1d

the top of the carrier substrate FIG. 1a when exposed to a second exposure radiation;

FIG. 2a

the carrier substrate FIG. 1 in section A - A 'with first functional layer applied thereon and first negative photoresist layer;

FIG. 2b

the carrier substrate FIG. 2a after structuring the photoresist layer and etching the first functional layer;

Figure 2c

the carrier substrate FIG. 2a after removal of the first photoresist layer in plan view;

Figure 2d

the carrier substrate Figure 2c with second functional layer and second positive photoresist layer applied thereto;

FIG. 2e

the carrier substrate Figure 2d after structuring the second photoresist layer and etching the second functional layer; and

FIG. 2f

the carrier substrate FIG. 2e after removal of the second photoresist layer in plan view.

FIG. 1a shows a carrier substrate 10 made of transparent PET, which has a prepared bottom 10 a. Figure 1 b shows the carrier substrate 10 from FIG. 1 a in section A - A '. The upper side of the carrier substrate 10 is designated by the reference numeral 10b. The underside 10a is provided in a first region 1 with a first diffractive relief structure and in a second region 2 with a second diffractive relief structure. For this purpose, as already explained above, the first and second relief structures are directly molded into the underside 10a of the carrier substrate, or the first and second relief structures are shaped into a replication lacquer layer provided on the underside. For example, each of the first and second relief structures is a sine grid having a relief depth of 400 nm and a grating period of 350 nm, wherein the grating lines of the sine grating of the first relief structure are arranged substantially perpendicular to the grating lines of the sine grating of the second relief structure. As can be seen from Table 2, for such sine gratings a degree of transparency of 82.3% for the TE polarization direction and 62.8% for the TM polarization direction results. When the first and second relief structures are illuminated, a relative difference in transparency of 30% results for the two different polarization directions.

Furthermore, it is also possible to use other diffraction structures with a grating period smaller than the wavelength of the light used for the irradiation for the first and second relief structures, in which the azimuth angle of the first and second relief structure differs and the Depth-to-width ratio of the relief structure is preferably greater than 0.3. In particular, the relief structures exemplified in Table 2 with a grating period of 350 nm and a depth of 100 nm or 800 nm can be used, in which case the azimuth angle of the first and second relief structures preferably has an angular difference of approximately 90 °.

On the first and second relief structures, a coating mask layer 100 of silver is sputtered over the entire surface in a constant area density with respect to the plane spanned by the carrier substrate 10.

The first region 1 is so oriented for a according to the grid lines of the first relief structure, TE polarized light more transparent than the second region. Conversely, the second region is more transparent to the 90 ° polarized light than the first region. In the third area, in which a superposition of the first and second relief structure is provided (here cross-shaped sine grid with a depth of 400 nm and a grating period of 350 nm), the higher transmittance exists for both polarization directions. If an exposure with linearly polarized light of a wavelength λ = 550 nm is selected as the first exposure radiation 20a, whose polarization direction is chosen so that the light is TE polarized with respect to the first relief structure, then there is a higher transparency (transparency) for the first exposure radiation 20a in the first and third areas. For a second exposure radiation 20b, which is an exposure to linearly polarized light having a wavelength of 550 nm and having a polarization direction rotated by 90 ° relative to the polarization direction of the exposure radiation 20a, increased transmittance results in the second region 2 and third area 3.

In a fourth region 4 without a relief structure, the exposure mask layer 100 is opaque and in a layer thickness, so that the fourth region 4 is impermeable to the first and the second exposure radiation 20a, 20b.

Figure 1c shows the top 10b of the carrier substrate 10 from FIG. 1a upon exposure of the lower surface 10a to the first exposure radiation 20a. In the first region 1, the exposure mask layer 100 has an increased permeability to the first exposure radiation 20a on the lower side 10a.

Figure 1d shows the top 10b of the carrier substrate 10 from FIG. 1a upon exposure of the bottom 10a to the second exposure radiation 20b. Only in the second region 2 does the exposure mask layer 100 have an increased permeability for the second exposure radiation 20b on the underside 10a.

FIG. 2a shows the carrier substrate 10 from FIG. 1a in section A - A 'with the first functional layer 30 of copper applied over its entire surface in a layer thickness of 0.1 .mu.m to 0.5 .mu.m and also a first negative photoresist layer 40 applied over the entire area. From the underside 10a of the carrier substrate 10, the first exposure radiation penetrates 20a amplifies in the first region 1 through the exposure mask layer 100, the carrier layer 10 and the first functional layer 30 and leads to a partially stronger exposure of the first photoresist layer 40. The exposure time and the exposure intensity are in this case matched to the photoresist used for the photoresist layer 40, that the photoresist is activated in the partially more exposed area 1, but is not activated in the less exposed areas 2 and 4.

The activated photoresist regions 40 'remain on the first functional layer 30 during the development and structuring of the photoresist and form an etching mask for the first functional layer 30.

FIG. 2b shows the carrier substrate 10 from FIG. 2a after etching the first functional layer 30. The regions of the first functional layer 30 which were not covered by the etching mask were removed, so that a structured first functional layer 30 'was formed.

Figure 2c shows the carrier substrate 10 from FIG. 2b after removal of the etching mask in plan view. The structured first functional layer 30 'is present on the upper side 10a of the carrier substrate 10 in register with the first region 1 (see FIG FIG. 1c) ,

Figure 2d shows the carrier substrate 10 from Figure 2c in cross-section, with a third functional layer 50 of a transparent organic dielectric material applied over the entire area on the structured first functional layer 30 'and free areas of the carrier substrate 10. On the whole surface, a second functional layer 31 made of copper in a layer thickness of 0.1 .mu.m to 0.5 .mu.m and a second positive photoresist layer 41 is also applied to the entire surface. From the lower side 10a of the carrier substrate 10, the second exposure radiation 20b penetrates in the second region 2 through the exposure mask layer 100, the carrier layer 10, the first functional layer 30, the third functional layer 50 and the second functional layer 31, resulting in a partially stronger exposure of the second exposure beam 20b second photoresist layer 41. The exposure time and the exposure intensity are hereby adjusted to the photoresist used for the photoresist layer 41 such that the photoresist is in the partially more exposed area 2 is activated, but not activated in the less exposed areas 1 and 4.

The non-activated photoresist regions 41 'remain on the second functional layer 31 during the development and structuring of the positive photoresist and form an etching mask for the second functional layer 31.

FIG. 2e shows the carrier substrate 10 from Figure 2d after development and structuring of the second photoresist layer or its remaining unexposed areas 41 ', and after etching of the second functional layer 31, wherein the structured second functional layer 31' was formed.

FIG. 2f shows the carrier substrate 10 from FIG. 2e after removal of the structured second photoresist layer 41 'in plan view. The structured second functional layer 31 'on the third functional layer 50 can be seen. The position of the structured first functional layer 30 'below the third functional layer 50 is indicated by a dotted line. The structured first functional layer 30 'is arranged in perfect register with the structured second functional layer 31'.

Claims (15)

1. Method for producing a multilayer body, in particular a multilayer body with at least one electronic structural element, wherein the multilayer body comprises at least two functional layers, in particular electrical functional layers, on a top side (10b) of a carrier substrate (10), which are structured in register with one another,
   characterised in that,
   an underside (10a) of the carrier substrate (10) is prepared in such a way that, in a first region (1), there results an increased level of transmissibility for a first exposure radiation (20a) compared to an at least one second region and, in at least one second region (2), there results an increased level of transmissibility for at least one second exposure radiation (20b) compared to the first region, which is different therefrom, in register with the first region (1), that the underside (10a) is successively exposed with the first and the at least one second exposure radiation (20a, 20b), and that the first exposure radiation (20a) is used for structuring a first functional layer (30) and the at least one second exposure radiation (20b) is used for structuring at least one second functional layer (31) on the top side (10b) of the carrier substrate (10).
2. Method according to claim 1,
   characterised in that,
   the underside (10a) of the carrier substrate (10) is prepared, while a first relief structure is formed in the first region (1) and, in register with the first relief structure, at least one second relief structure that differs from the first relief structure is formed in the second region (2), that, furthermore, an exposure mask layer (100) is applied to the underside (10a), wherein the exposure mask layer (100) is applied with a constant areal density with respect to a plane that is fixed by the carrier substrate (10), that the first functional layer (30) applied to the top side (10b) of the carrier substrate (10) is structured in register with the first relief structure, and that the at least one second electrical functional layer (31) applied to the top side (10b) of the carrier substrate (10) is structured in register with the at least one second relief structure.
3. Method according to claim 2,
   characterised in that,
   the exposure mask layer (100) is formed from a metallic layer or from a layer made from a metal alloy.
4. Method according to one of the preceding claims,
   characterised in that,
   the first and the second relief structure are formed by diffractive relief structures with a depth-to-width ratio of the individual structural elements of = 0.3.
5. Method according to one of the preceding claims,
   characterised in that,
   the first and second relief structures are formed from relief structures with a grating period of =800nm, preferably =500nm.
6. Method according to claim 1,
   characterised in that,
   the underside (10a) of the carrier substrate (10) is prepared, while a first relief structure is formed in the first region (1) and at least one second relief structure that differs from the first relief structure is formed in the second region (2) and in register with the first relief structure, that the first functional layer (30) applied to the top side (10b) of the carrier substrate (10) is structured in register with the first relief structure, and that the at least one second electrical functional layer (31) applied to the top side (10b) of the carrier substrate (10) is structured in register with the at least one second relief structure.
7. Method according to claim 1,
   characterised in that,
   the underside (10a) of the carrier substrate (10) is prepared, while a first layer of paint is arranged in the first region and at least one second layer of paint that differs from the first layer of paint in terms of colour is arranged in the second region and in register with the first layer of paint, and that the first functional layer applied to the top side (10b) of the carrier substrate (10) is structured in register with the first layer of paint, and that the at least one second functional layer applied to the top side (10b) of the carrier substrate (10) is structured in register with the at least one second layer of paint.
8. Method according to one of claims 1 to 7,
   characterised in that,
   the structured first functional layer (30') is formed from an electrically conductive functional layer material.
9. Method according to one of claims 1 to 8,
   characterised in that,
   the structured second functional layer (31') is formed from an electrically conductive or a semi-conductive or a dielectric functional material.
10. Multilayer body, in particular multilayer body with at least one organic, electronic structural element, which has a carrier substrate (10),
    characterised in that,
    an underside (10a) of the carrier substrate (10) is prepared in such a way that, in a first region (1), an increased level of transmissibility for a first exposure radiation (20a) compared to an at least one second region and, in at least one second region (2), an increased level of transmissibility for at least one second exposure radiation (20b) compared to the first region, is formed, and that two separately structured functional layers (30', 31') are arranged on a top side (10b) of the carrier substrate (10), with which a first functional layer (30) is structured, such that the first functional layer (30') is arranged in register with the first region, and wherein a second functional layer (31') is structured, such that the second functional layer (31') is arranged in register with the second region (2).
11. Multilayer body according to claim 10,
    characterised in that,
    a first relief structure is arranged in the first region (1) and at least one second relief structure that differs from the first relief structure is arranged in the second region (2) and in register with the first relief structure.
12. Multilayer body according to one of claims 10 or 11,
    characterised in that,
    furthermore, an exposure mask layer (100) is arranged on the underside (10a).
13. Multilayer body according to claim 12,
    characterised in that,
    a first layer of paint is arranged in the first region (1) and at least one second layer of paint that differs from the first layer of paint in terms of colour is arranged in the second region (2) and in register with the first layer of paint.
14. Multilayer body according to one of claims 10 to 13,
    characterised in that,
    the multilayer body has one or more electrical structural elements, in particular a capacitor, a field effect transistor, a solar cell, a structural element containing a photosensitive layer, a resistor, an antenna, an LED, in particular an OLED, or a diode.
15. Multilayer body according to one of claims 10 to 14,
    characterised in that,
    the multilayer body has a glass layer as a substrate, and that the multilayer body has a replicating varnish layer, into which a first diffractive relief structure is moulded in the first region, and into which a second diffractive relief structure, which is different thereto, is moulded in the at least one further second region.

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